Generally, for adapting to AC cables with different specifications and sizes in various countries, an adapter usually includes an AC inlet for electrically connecting to other electronic apparatuses. According to international IC 320 standard safety temperature value, the operation temperature of the AC inlet of the adapter for connecting different AC cables of various countries should be lower than the standard such as 78° C. The adapter used in electronic products will consume partial electric power when being operated. Furthermore, along with the technology development of electronic products, more and more electric units are loaded on the printed circuit board inside the electronic product, resulting in increasing the integration of the electric units. Currently, the electric power for operating most adapters has increased to 100˜200 Watts, even over 200 Watts. Since the Watt consumption increases, it is inevitably that the temperature of the whole adapter is increased due to the heat generated from adapter operation. It also increases the difficulty for solving the temperature problem of the AC inlet. It is necessary to consider the international standard safety temperature value of the AC inlet when the adapter is designed and manufactured. Therefore, for complying with the standard, the internal structure of adapter must improve the heat dissipating effect, for example the DC fan addition. However, it causes the cost increase and the structure change of the AC inlet.
Therefore, the purpose of the present invention is to develop an adapter having an AC inlet with heat insulation function for efficiently insulating the heat generated from the adapter to deal with the above problems encountered in the prior art.